Lecture Essential vs. Accidental Properties PDF

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Lecture about Essential vs. Accidental Properties...

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Essential vs. Accidental Properties The distinction between essential versus accidental properties has been characterized in various ways, but it is often understood in modal terms: an essential property of an object is a property that it must have, while an accidental property of an object is one that it happens to have but that it could lack. Let’s call this the basic modal characterization, where a modal characterization of a notion is one that explains the notion in terms of necessity/possibility. In the characterization just given of the distinction between essential and accidental properties, the use of the word “must” reflects the fact that necessity is invoked, while the use of the word “could” reflects that possibility is invoked. The notions of necessity and possibility are interdefinable: to say that something is necessary is to say that its negation is not possible; to say that something is possible is to say that its negation is not necessary; to say that an object must have a certain property is to say that it could not lack it; and to say that an object could have a certain property is to say that it is not the case that it must lack it. Many would say that each individual human could not fail to be human; if so, then the basic modal characterization counts the property of being human as an essential property of each human. And, too, many would say that although someone, say Socrates, is in fact fond of dogs, Socrates could have lacked that property; if that is right, then the basic modal characterization counts the property of being fond of dogs as an accidental property of Socrates. A modal characterization of the distinction between essential and accidental properties is taken for granted in nearly all work in analytic metaphysics in the latter half of the 20th century. Advocates of the modal characterization have included Ruth Barcan Marcus (1967) and Saul Kripke (1972/1980), among others. However, some other characterizations of the distinction (see §2) have recently gained currency. It is worth stressing here at the outset that although there is now some disagreement about how the distinction between essential and accidental properties is to be drawn, there is nevertheless some agreement about cases. Most would agree that however the distinction is drawn, it should come out that being human (or being human if existent) is an essential property of Socrates while being fond of dogs is a merely accidental property of Socrates.

Essentialism in general may be characterized as the doctrine that (at least some) objects have (at least some) essential properties. This characterization is not universally accepted (see §3), but no characterization is; and at least this one has the virtue of being simple and straightforward. As for specific essentialist claims, we have already encountered one—the claim that the property of being human is essential to Socrates. Another example is the claim that Socrates’s biological origin—Socrates’s parents, or more particularly, the sperm and egg from which Socrates arose—is essential to Socrates. The first example is a brand of sortal essentialism while the second is a brand of origin essentialism. Both of these kinds of essentialisms have figured prominently in the philosophical literature. 1. The Modal Characterization of the Essential/Accidental Property Distinction According to the basic modal characterization of the distinction between essential and accidental properties, which is the characterization given at the outset, PP is an essential property of an object oo just in case it is necessary that oo has PP, whereas PP is an accidental property of an object oo just in case oo has PP but it is possible that oo lacks PP. Putting this into the language of possible worlds that philosophers often adopt, PP is an essential property of an object oo just in case oo has PP in all possible worlds, whereas PP is an accidental property of an object oo just in case oo has PP but there is a possible world in which oo lacks PP. Although the basic idea behind the modal characterization is clear enough from these statements, a moment’s reflection reveals a little bit of trouble. Many properties (some philosophers would say all properties) are such that in order for an object to possess them, that object must exist. According to the basic modal characterization, any such property, if possessed by a contingently existing object, will be counted as an accidental property of that object. But this seems wrong. Consider the property of being a dog. It is plausible (and for present purposes we assume it is true) that an object must exist in order to possess this property. Now consider a particular dog named ‘Emma’, who in fact exists but who might not have existed. There is a possible world in which Emma does not exist. And in this world (given our assumption) Emma is not a dog, since Emma does not exist there. So, according to the basic modal characterization, being a dog is an accidental property of Emma. But however we characterize the distinction between essential and accidental properties, the characterization should not by itself rule out the intuitively compelling claim that Emma is essentially a dog. So the basic modal characterization seems flawed.

In response to this point, it is tempting to turn to a variant of the basic modal characterization, the existence-conditioned modal characterization, according to which PP is an essential property of an object oo just in case oo has PP and it is necessary that oo has PP if oo exists, whereas PP is an accidental property of an object oo just in case oo has PP but it is possible that oo lacks PP and yet exists. But this formulation too is less than satisfactory. A widely noted problem for this way of drawing the distinction is that it makes existence into an essential property of each object, since no object could lack existence and yet exist. Thus, this characterization of the essential/accidental property distinction effectively rules out a theist’s claim that only God has existence as an essential property. But a good characterization of the distinction should not rule on a substantive matter in this way. Arguably neither of these problems is devastating. Those who favor the basic characterization can say that typically when someone claims, for example, that Emma is essentially a dog, what is really meant is not that Emma has essentially the property of being a dog, but instead that Emma has essentially the property of being a dog if existent. Existence will be treated specially on this approach: the claim that an object has existence as an essential property will not be taken as the claim that the object has as an essential property the property of being existent if existent; instead the claim will be taken at face value. Those who favor the existence-conditioned characterization can say that when someone says that only God has existence as an essential property, what is really meant is that only God has existence as a necessary property, where a necessary property of an object is a property that the object possesses in all possible worlds. (According to the basic modal characterization, an essential property is the same as a necessary property.) Both approaches may be faulted for making a special case of the property of existence. But that is not perhaps such a great fault, given that existence does seem to be a special case and that it is treated specially in other areas of philosophy as well. (It is perhaps worth pointing out that according to many philosophers—Kant, Russell, and Frege to name three—existence is not a property at all. If this is right, then existence is indeed a very special case.) In what follows, we shall not be concerned with the details arising from the need for some sort of existence condition—either in the statement of the definition of an essential property (as on the existence-conditioned modal characterization) or in the properties that are taken to be essential (as on the basic modal characterization). There are other ways of explaining the distinction between essential and accidental properties of objects in modal terms (to be discussed in §2), but what we have called the basic modal characterization and the existence-conditioned modal characterization are the standard ways. Together, usually indiscriminately, these amount to what we call the modal characterization.

The central notion involved in any modal characterization of the distinction between essential and accidental properties is that of metaphysical necessity/possibility. But, since there are a number of notions that correspond to the many ways that we use the words ‘necessity’ and ‘possibility’, it is helpful to contrast the relevant notion of necessity/possibility with some other notions with which it might be confused. If one claims that something is possible, it is sometimes natural to take this to mean that one does not know it to be false. For example, suppose that you ask someone whether Socrates ever went to Sparta and she answers that it is possible. It is natural to understand her as saying that she does not know that Socrates did not go to Sparta. Thus, the possibility that is expressed here is a kind of epistemic possibility (in particular, one according to which pp is epistemically possible for an agent XX just in case not-pp is not known by X)X). This notion of epistemic possibility is clearly distinct from the notion of metaphysical possibility, since there are cases of epistemic possibilities that are not metaphysical possibilities. Of Goldbach’s Conjecture (that every even number greater than two is the sum of two primes) and its denial, each is epistemically possible but one (we know not which) is not metaphysically possible. And there are cases of metaphysical possibilities that are not epistemic possibilities. That there are only two planets in our solar system is metaphysically possible but not epistemically possible for most of us, given that most of us know that there are not only two planets in our solar system. (This is not to deny that there may be some notions of epistemic possibility—for example, maximally complete ways the universe can coherently be conceived to be—for which it is at least plausible to suppose that every metaphysical possibility is also an epistemic possibility. Even if this is so, the notions of metaphysical possibility and epistemic possibility are distinct.) In addition to various notions of epistemic possibility, philosophers have been concerned with three particular notions of possibility that are generally regarded as non-epistemic: logical possibility, metaphysical possibility, and physical possibility. On one common view, the physical possibilities are a subset of the metaphysical possibilities, which in turn are a subset of the logical possibilities. (But see Fine (2002) for an opposing view.) Here are a couple of examples of things that are logically possible but neither metaphysically nor physically possible: the Eiffel Tower’s being red all over and green all over at the same time; the Eiffel Tower’s being red but not extended.[1] Here is an example of something that is logically and metaphysically possible but not physically possible: the Eiffel Tower’s traveling faster than the speed of light. The Eiffel Tower’s being both red and not red at the same time is possible in none of the senses while its traveling faster than a speeding bullet is possible in all of them. To supplement these examples, it would be nice to give characterizations of the three notions that are free from controversy. That is easier said than

done. Nonetheless, we offer some characterizations that are relatively uncontroversial. Metaphysical possibility is often taken as a primitive notion that figures into the idea of a physical possibility: a proposition is physically possible if and only if it is metaphysically compossible with the laws of physics. (Other nomological possibilities, such as chemical or biological possibility, can be understood similarly.) Assuming that the notion of a logical truth is understood, then the logical necessities are simply the logical truths, so that the logical possibilities are those things whose negations are not logical truths. We end this overview of the modal characterization of the essential/accidental property distinction by mentioning a notion that is close to, but different from, that of an essential property. It is easy to confuse the notion of an essential property—a property that a thing could not lack—with the notion of a property that a thing could not lose, so it is worth taking a minute to reflect on the difference. Of course, any property that a person could not lack is one that that person could not lose, since by losing a property the person comes to lack it. Still, the “reverse” does not hold. There are properties that a person could not lose—like the property of having spent Christmas 2007 in Tennessee—that are nevertheless not essential to that person. 2. Other Ways of Characterizing the Essential/Accidental Property Distinction The modal characterization of an essential property of an object as a property that an object must possess fits well with (at least one aspect of) our everyday understanding of the notion of essentiality, which often seems simply to be the notion of necessity. To say that something is essential for something else is typically just to say that the first is necessary for the second. But however well this account fits with (this aspect of) our everyday understanding of essentiality, it has some consequences that may be surprising: this characterization classifies the property of being such that there are infinitely many primes (or, perhaps, being such that there are infinitely many primes if the thing in question is existent) as essential to Socrates (as well as to all other things), since Socrates (like all other things) must have this property. Socrates must have this property for the simple reason that it is necessary that there are infinitely many primes. Moreover, this characterization classifies the property of being the sole member of the unit set {2}{2} as essential to the number 2, given that it is necessary that 2 is the sole member of the unit set {2}{2}. Some philosophers, most prominently Kit Fine (1994), have found these results disturbing. Fine thinks that the notion of an essential property of a thing should be bound up with the notion of the thing’s nature or what it is to be that thing, but, Fine thinks, being such that there are infinitely many primes intuitively has nothing to do with what it is to be Socrates. And although it seems that having the number 2 as its sole member is part of

what it is to be the unit set {2}{2}, it does not seem that being this unit set’s sole member is part of what it is to be the number 2. It is Fine’s view that these sorts of properties are counterexamples to the modal characterization.[2][3] To replace the modal characterization, Fine offers a definitional characterization of essential properties, according to which the essential properties of an object are those of its properties that are part of the object’s “definition”. What exactly is a “definition” of an object? This is a difficult question. At first sight, it seems to be a category mistake: it is words and perhaps concepts—but not objects—that have definitions. Even so, it must be admitted that some objects—such as the number 2 and the unit set {2}{2}—do seem to be definable: it is plausible to think that the number 2 is defined as being the successor of the number 1; and it is plausible to think that the unit set {2}{2} is defined as being the set whose sole member is the number 2. But other objects—such as Socrates—do not seem to admit so readily of definition. So even if the notion is understood well enough for some objects (never mind that not everyone would allow that the number 2, for example, is an object), a major challenge for the advocate of the definitional characterization is to provide a respectable general understanding of the notion of a definition for an object. Another issue bears mentioning inasmuch as the present article concerns the distinction between essential and accidental properties and not merely different ways that one may characterize what an essential property is. There is a recognized analytic connection between the terms ‘essential property’ and ‘accidental property’ such that the properties of a given thing divide exclusively and exhaustively into the categories essential and accidental. Although the thought that a thing’s essential properties are those that are a part of its definition has caught on in the philosophical literature, the thought that a thing’s accidental properties are those of its properties that are not part of its definition has not. For example, few would say that it is merely accidental to Socrates to be the sole member of {Socrates}{Socrates}. In short, the phrase ‘accidental property’ tends to be used in the sense of a modally accidental property. Several philosophers have defended non-standard versions of the modal characterization in light of Fine’s putative counterexamples. Edward Zalta (2006) was among the first. He distinguishes between abstract objects (such as numbers and fictional characters) and ordinary objects (such as Socrates). According to Zalta, every object necessarily exists (whether abstract or ordinary), but ordinary objects are not necessarily concrete. Indeed, an ordinary object such as Socrates is concrete in some possible worlds but nonconcrete in others. Zalta suggests two separate accounts of essence, one corresponding to abstract objects and the other corresponding to ordinary objects. Here is Zalta’s account of essence for ordinary objects, slightly simplified:

PP is an essential property of an ordinary object oo just in case (1) it is necessary that oo has PP if oo is concrete, and (2) it is not necessary that oo has PP. In all possible worlds, Socrates is such that there are infinitely many primes (whether Socrates is concrete or non-concrete). Thus, condition (2) is not satisfied. Thus, this is not one of Socrates’s essential properties. (In Zalta’s terminology, this is not one of Socrates’s strongly essential properties, although Zalta would say that it is one of Socrates’s weakly essential properties, since condition (1) is satisfied.) Here is Zalta’s account of essence for abstract objects: PP is an essential property of an abstract object oo just in case it is necessary that oo encodes PP. Only abstract objects are capable of encoding properties, according to Zalta. To say that an abstract object encodes a property is to say that the property is included in our conception of the object. Thus, the fictional character Sherlock Holmes encodes the property of being a detective, even though Sherlock Holmes does not have this property. (In Zalta’s terminology, Sherlock Holmes does not exemplify this property. Sherlock Holmes exemplifies properties such as being created by Arthur Conan Doyle and having been portrayed by Jeremy Brett.) According to Zalta, being a detective is one of Sherlock Holmes’s essential properties. In contrast, being such that there are infinitely many primes is not one of Sherlock Holmes’s essential properties, since this property is not included in our conception of Sherlock Holmes. The asymmetry between the essential properties of Socrates, who is an ordinary object, and {Socrates}, which is an abstract object, is explained: given the theory and definitions proposed, it is not essential to Socrates that he is an element of {Socrates}, but it is essential to {Socrates} that Socrates is an element of it (see Zalta 2006, §5, for the details). Fabrice Correia (2007) suggests a different version of the modal characterization, based on a non-standard conception of modality: PP is an essential property of an object oo just in case it is locally necessary that oo has PP if there are facts about oo. In order to understand this characterization, we must first understand Correia’s non-standard conception of modality, inspired by Arthur Prior (1957). Philosophers typically regard possible worlds as giving a complete description of a possible state of the universe. These are what Correia calls globally possible worlds. Loca...